Problem: $ { \left[\begin{array}{rrr}{0} & {-1} & {1} \\ {1} & {2} & {3}\end{array}\right]-\left[\begin{array}{rrr}{1} & {3} & {1} \\ {-2} & {-1} & {4}\end{array}\right] = {?} } $
Answer: To find the difference of two matrices, subtract the corresponding items between each matrix. ${\left[\begin{array}{rrr}{0}-{1} & {-1}-{3} & {1}-{1} \\ {1}-{-2} & {2}-{-1} & {3}-{4}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rrr}{-1} & {-4} & {0} \\ {3} & {3} & {-1}\end{array}\right]}$